1. Technical Field of the Invention
The present invention relates to liquid processing apparatus and method by which a designated liquid processing is applied on a variety of substrates, for example, semiconductor wafer, LCD glass substrate, etc.
2. Description of the Related Art
In the manufacturing process of semiconductor devices, for example, there is used a cleaning system where a semiconductor wafer is cleaned to remove contaminations (particles, organic contaminants, metallic impurities, etc.) from the wafer and remove polymer etc. after an etching process by using a cleaning liquid, such as designated chemical liquid and deionized (pure) water.
As one wafer cleaning apparatus provided in the cleaning system, there is a known single-wafer type cleaning apparatus where a wafer is retained substantially horizontally and cleaned in rotation. For example, Japanese Patent Publication No. 8-78368 discloses a wafer cleaning apparatus where a wafer is supported by a plurality of support pins on a spin chuck and additionally, a cleaning liquid is supplied to the front face of the wafer and also a clearance between the wafer and the spin chuck, thereby cleaning both sides of the wafer simultaneously.
In the cleaning apparatus disclosed in Japanese Patent Publication No. 8-78368, however, there is a problem of insufficient cleaning since the cleaning liquid cannot spread up to wafer""s portions in abutment with the support pins.
Under the above-mentioned situation, an object of the present invention is to provide liquid processing apparatus and method by which it becomes possible to prevent an occurrence of unprocessed portions on a substrate subjected to a liquid processing.
In order to accomplish the above object, there is provided, according to an invention stated in claim 1, a liquid processing apparatus for applying a liquid processing on a substrate by a processing liquid, comprising: supporting device for supporting the substrate substantially horizontally; holding device for holding an end face of the substrate and moving the substrate to and from the supporting device, the holding device being capable of holding the substrate substantially horizontally while the substrate is away from and above the supporting device by a predetermined distance; and processing-liquid supply unit for supplying the substrate held by the holding device with a processing liquid.
According to an invention stated in claim 2, there is also provided a liquid processing apparatus for applying a liquid processing on a substrate by a processing liquid, comprising: a rotary plate capable of rotation; a supporting member arranged on the rotary plate to substantially horizontally support the substrate at a predetermined position of the periphery of the substrate; a holding member arranged on the rotary plate to hold the substrate substantially horizontally; processing-liquid supply unit for supplying the substrate held by the holding member with a processing liquid; a driving mechanism for moving the holding member so that the substrate, which has been supported by the supporting member, can be held apart from the supporting member by the holding member and that the substrate, which has been held by the holding member, can be supported apart from the holding member by the supporting member; and a holding mechanism for holding the holding member at a predetermined position so that the substrate is held apart from the supporting member by the holding member.
According to an invention stated in claim 3, the holding member is provided with a claw part which holds an end face of the substrate, and the claw part has wall portions each inclined to the substrate with a predetermined angle, the wall portions being adapted to abut on circumferential edges of the substrate obliquely from its upside and downside respectively, in a manner that the circumferential edges of the substrate are pinched between the wall portions.
According to an invention stated in claim 4, the claw parts are arranged in two positions of the holding member apart from each other in a horizontal direction.
According to an invention stated in claim 5, the claw part is adapted so that the lower wall portion receives one of the circumferential edges of the substrate when the substrate is moved between the supporting member and the holding member, and the claw part is adapted so that the upper wall portion and the lower wall portion pinch the circumferential edges of the substrate when the substrate is away from the supporting member.
According to an invention stated in claim 6, the holding member comprises a main body formed to project from the rotary plate upward, the main body being provided, at a tip thereof, with the claw part and a base part arranged on the underside of the main body, the base part being connected with the main body; the holding mechanism includes a connecting member formed on a lower face of the rotary plate to connect the base part with the rotary plate so that the holding member can rotate with a predetermined angle and a spring disposed between the base part and the rotary plate to hold the holding member at a position and provide the claw part with a predetermined force for holding the substrate; and the driving mechanism includes a pressing member to press the base part toward the rotary plate thereby releasing the predetermined force for holding the substrate, the predetermined force being applied on the claw part by the spring.
According to an invention stated in claim 7, the holding member is formed to have a center of gravity in level with a rotating center of the holding member under condition that the claw part holds the substrate.
According to an invention stated in claim 8, the base part is provided, inside thereof, with a weight member for adjusting the position of a center of gravity of the holding member, the weight member having a specific gravity larger than a specific gravity of the other portion of the base part.
According to an invention stated in claim 9, the main body has side faces each tapered with a predetermined angle or curved in plan view, thereby reducing an air resistance exerted to the main body when the rotary plate is rotated.
According to an invention stated in claim 10, the supporting member includes a supporting part for contact with the back face of the substrate and a wall part having a predetermined height to guide a circumferential end face of the substrate supported by the supporting part; and the holding member is adapted so as to hold the substrate in a position where the back face of the substrate is away from the supporting part of the supporting member and where a level of the back face of the substrate is lower than the top of the wall part of the supporting member.
According to an invention stated in claim 11, the rotary plate is provided, in a periphery thereof and at designated positions about the periphery, with notches in which the supporting member and the holding member are provided.
According to an invention stated in claim 12, the liquid processing apparatus further comprises: a first plate arranged apart from the back face of the substrate in a predetermined distance so as to be substantially parallel with the back face of the substrate held by the holding member; and a second plate which is movable up and down thereby occupying a position where the second plate is arranged apart from the front face of the substrate in a predetermined distance so as to be substantially parallel with the front face of the substrate held by the holding member, wherein the processing-liquid supply unit can supply the processing liquid into a clearance defined between the first plate and the back face of the substrate and another clearance defined between the second plate and the front face of the substrate.
According to an invention stated in claim 13, there is also provided a liquid processing apparatus for applying a liquid processing on a substrate by a processing liquid, comprising: a rotary plate capable of rotation; a holding-member body arranged on an outer periphery of the rotary plate, the holding-member body being rotatable about a rotating shaft in parallel with a rotating shaft of the rotary plate; a supporting part provided in the holding-member body to support the substrate at a predetermined position of a peripheral part of the substrate substantially horizontally; a pressing part provided in the holding-member body to press the outer periphery of the substrate supported by the supporting part inward in a radial direction thereof; a holding part provided in the holding-member body to hold the outer periphery of the substrate substantially horizontally; a processing-liquid supplying unit for supplying the substrate held by the holding part with a processing liquid; a fixing mechanism for fixing the holding-member body in a predetermined position so as to allow the substrate to be supported by the supporting part; an urging mechanism for rotating the holding-member body so that when releasing the fixing mechanism, the pressing member can press the substrate while the substrate is being supported by the supporting part; and a centrifugal weight for rotating the holding-member body by means of a centrifugal force so as to make the pressing part withdraw from the outer periphery of the wafer, make the holding part to engage with the outer periphery of the wafer and support the substrate being away from the supporting part.
According to an invention stated in claim 14, there is further provided a liquid processing apparatus for applying a liquid processing on a substrate by a processing liquid, comprising: a rotary plate capable of rotation; a holding-member body arranged on an outer periphery of the rotary plate, the holding-member body being rotatable about a rotating shaft in parallel with a rotating shaft of the rotary plate; a supporting part provided in the holding-member body to support the substrate at a predetermined position of a peripheral part of the substrate substantially horizontally; a holding part provided in the holding-member body to hold the substrate substantially horizontally; a processing-liquid supplying unit for supplying the substrate held by the holding part with a processing liquid; a driving mechanism for rotating the holding-member body so that the substrate that has been held by the holding part is supported by the supporting part while the substrate is being away from the holding part; and an urging mechanism for rotating the holding-member to a predetermined position so that the substrate that has been supported by the supporting part is held by the holding part while the substrate is being away from the supporting part.
According to an invention stated in claim 15, in the liquid processing apparatus, a position to allow the supporting part to support the substrate is higher than another position to allow the holding part to hold the substrate.
According to an invention stated in claim 16, the holding part has a groove formed to have a V-shaped section defined by two inclined faces; and the substrate is held in a manner that a ridgeline where the upper face of the substrate intersects the outer circumferential face of the substrate and another ridgeline where the lower face of the substrate intersects the outer circumferential face of the substrate come into contact with the inclined faces of the holding part, respectively.
According to an invention stated in claim 17, there is also provided a liquid processing method of applying a liquid processing on a substrate, the method comprising: a first process to allow a supporting member for supporting the substrate to support the substrate substantially horizontally; a second process to allow a holding member for holding the substrate to hold the substrate substantially horizontally while the substrate is being away from the supporting member; and a third process to supply the substrate held by the holding member with a processing liquid, thereby restraining an occurrence of unprocessed portions on the substrate, which might be caused since the supporting member abuts on the back face of the substrate.
According to an invention stated in claim 18, there is further provided a liquid processing method of applying a liquid processing on a substrate, the method comprising: a first process to allow a supporting member for supporting the substrate to support the substrate substantially horizontally; a second process to allow a holding member for holding the substrate to hold the substrate substantially horizontally while the substrate is being away from the supporting member; a third process to arrange a plate member so as to be substantially parallel with the back face of the substrate held by the holding member, at a predetermined distance; a fourth process to supply a gap between the back face of the substrate held by the holding member and the plate member with a processing liquid; and a fifth process to rotate the substrate held by the holding member, at a predetermined rotating speed, thereby restraining an occurrence of unprocessed portions on the substrate, which might be caused since the supporting member abuts on the back face of the substrate.
According to an invention stated in claim 19, in the above method, the fourth process includes the steps of: forming a paddle of the processing liquid between the back face of the substrate held by the holding member and the plate member; and retaining the paddle therebetween for a predetermined period.
According to an invention stated in claim 20, the third process further includes the step of arranging another plate member so as to be substantially parallel with the front face of the substrate held by the holding member, at a predetermined distance; and the fourth process further includes the step of supplying a gap between the front face of the substrate held by the holding member and the other plate member with a processing liquid.
According to the liquid processing apparatuses and methods mentioned above, it is possible to prevent an occurrence of unprocessed portions on the substrate due to insufficient diffusion of the processing liquid. Because the liquid processing can be performed on condition of not supporting the substrate but holding a circumferential end face thereof. In conclusion, it is possible to establish a uniform liquid processing for the substrate.
The above and other features and advantages of this invention will become apparent, and the invention itself will best be understood, from a study of the following description and appended claims, with reference had to the attached drawings showing preferred embodiments of the invention.